Disinfection apparatus of the above type are well known and are also called washer disinfectors. They are used for cleaning and disinfection of goods, instruments and other objects that are used in, for instance, hospitals, laboratories and in the pharmaceutical industry. In these fields disinfection is an important activity, for instance, to prevent the spread of infection and bacterial growth. As examples of objects that need be disinfected, mention can be made of vessels, instrument containers, hospital beds, trolleys, wheelchairs, animal cages, machine parts for health care applications and other bulky objects.
One type of disinfection apparatus is provided with what is referred to as walk-in chambers, which are large enough for an individual to enter and/or large enough for a trolley/cart or other equipment to be inserted.
Washer disinfectors of this kind usually have a disinfection chamber into which a plurality of nozzles open. The nozzles are connected via, for instance, a high-pressure pump to a separate liquid tank. The disinfection chamber usually has a liquid-permeable chamber floor mounted over the bottom of the chamber, on which chamber floor objects are placed to be cleaned. In liquid cleaning of objects in the chamber, the descending liquid is collected at the bottom of the chamber, and the liquid flows to a second pump, which is sometimes also referred to as a sump pump, which makes it possible to pump the liquid out of the liquid system, or alternatively return the liquid to the liquid system.
Disinfectors of this type are usually installed in a chamber cavity, which is also referred to as a pit, in the installation floor so that the liquid-permeable chamber floor and the surrounding floor outside the entrance to the chamber are positioned at the same level. In this case, it is desirable to reduce said cavity in the floor without deteriorating the intended function of the wash disinfector.
Alternatively, the washer disinfector can be installed as a separate unit directly on the floor with an adjusted and associated ramp in front of the entrance to the chamber to allow objects, for instance on trolleys, to be moved into and out of the chamber. For reasons of comfort for instance, it is desirable that said ramp be as low as possible.
In both cases, it is thus desirable to reduce the so-called installation height, i.e. the difference in height between the liquid-permeable chamber floor and the bottom of the chamber. However, the sump pump limits the possibilities of reducing the installation height since at low liquid levels it tends to at least partly draw in air, thereby deteriorating the intended function of the pump.
Several solutions have been tested to solve the above problems. For instance, in addition to said cavity, a further recess (ascending pipe) has been arranged at the inlet of the pump to collect a liquid column in order to ensure that the sump pump obtains sufficient liquid and, thus, reduce the risk of the sump pump drawing in air. However, the drawback is that not all installation floors allow such deep recesses, for instance for reasons of construction. It is also advantageous to be able to replace an old disinfection apparatus with a new one without the floor below having to be greatly modified, as described above.
Washer disinfectors further usually have a process step, in which the liquid is heated before being supplied to the chamber. To allow quick heating and to obtain a quick cleaning step, it is desirable to have a small but sufficient liquid volume in the system. Thus, there is a need to reduce the use of liquid tanks and at the same time have a sufficient volume in the system, so that on the one hand the required cleanness is achieved and, on the other, the sump pump works according to its intended function. Moreover it is desirable to be able to reduce the number of machine components of the disinfection apparatus and yet maintain its desired disinfection function.
Finally it is advantageous to provide a robust, cost-effective and reliable high quality disinfection apparatus.